Typewriting machine



June 5, 1923. 31,457,985

L. J. DU MAIS 1 TYPEWRITING MACHINE Filed Nov. 1 1920 2 Sheets-Sheet l June 5, 1923.

L. J. DU MAIS TYPEWRITING MACHINE Filed Nov. 1 1920 2 Sheets-Sheet 2 Patented June 5, i923.

earner eerie LEO J. DU MAIS, OF CHICAGO, ILLINOIS, ASSIGNOR 'IO GARBELL TYPEVJRITER CORPO- BATION, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

TYPEWBITING MACHINE.

Application filed November 1, 1920. Serial No. 420,886.

T 0 all whom it may concern:

Be it known that I, Leo J. DU Mars, :1 citizen of the United States, residing Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Typewriting Ma chines, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to innn'ovements in typewriting machines, and more particularly to that type of typewriters employing thrust or reciprocating type bars, as exemplified in Garbell Patent 1,305,893, issued June 8, 1919, and, more specifically, is concerned with the means for guiding the type bars.

An object of'the invention is to provide practical, eiiicient, durable and economical guiding means, individually and adjustably associated with each type bar to thereby compensate for variations, within limits of commercial practice occurring in manufacture of the parts, and for wear arising in use so that a smooth and accurate type bar action for the type bar is at all times insured.

Qther objects of the invention will more clearly appear from the description herein after following.

In the drawings forming a part of this specification, Figure 1 is a broken, top plan view of a typewriter showing my improvements in connection therewith, the usual cover plate being omitted as well as non-es sential details of various parts of the typewriter not necessary tobe illustrated in eX- plaining the invention. Figure? is a vertical, sectional view corresponding substan tially to the line 2-2 of Figure 1. Figure 3 is a detail view corresponding to the section line of Figure 2 illustrating more clearly certain details of the construction. In Fig ure 3 the full lines indicate the normal posi* tion of the type bar and actuating segmental gear, and the dotted lines indicate the printing positionof the type bar. Figures 4 and 5 are enlarged detail sectional views corresponding respectively to lines 4& and 55 of Figure 3. Figure 6 is a group perspective of the elements, separated, composing a single type bar, parts being broken away. Figure? is a perspective of the rear portion of a type bar in its assembled condition. And Figure 8 is a View corresponding to Figure 5 illustrating another embodiment of my invention.

are arranged in the usual manner and each is formed at its inner end with a notch as indicated at by which the lever is loosely fulcrumed in a correspondingly notched fulcrum bar 16, secured to the frame A... Each key lever E also has a stud 17 on its under side over which seats one end of a return spring 18, the lower end of each spring 18 being seated over an adjustable screw 19 mounted in a supporting bracket 20 carried by the frame. By adjusting the screw 19, it is obvious that the pressure on the type key levers may be varied to produce the desired touch and that the springs will hold the key levers in operative engagement with the fulcrum bar 16. The key levers are limited in their upward movement, that is, in their return to normal position by engagement with a pad 21 carrier by bracket 22 extending transversely of the frame.

Only such portion of the platen B has been shown as is necessary to an understanding of the invention but as will be understood by those skilled in the art, said platen will be carried in the usual manner by a roll carriage movable laterally of the machine, the platen itself being vertically adjustable for the different lease letters and numerals on the type bars. It will also be understood that the usual spacer bar, shift keysfetc. may be employed.

As clearly shown in Figure 1, the type bars C reciprocate horizontally and. are arranged in a segmental group, each type bar reciprocatin in a line corresponding to a radius of a circle the center of which coincides with the printing point as indicated at 23. "Each of said type bars C carries at its inner end, that is, the end nearest the platen, a type block 24 provided with the printing characters indicated at 2525, said type block also having guiding ends 26-26, cooperable with the upper and lower converging centering guides 27-27, the lower centering guide 27 being mounted on the plate 14 and the upper centering guide 27 being carried by an upstanding bracket 28.

In addition to the type block 24, each type bar C comprises a mainstamped element 29 and two plates 30-30, as shown best in Figures 6 and 7 The main element 29 is of generally rectangular formation from the upper portion of which is extended rearwardly an arm 31 having a-s'eries of rack teeth 32 on the under side thereof. The upper edge 33 of the arm 31 is cut awayor depressed below the upper edge 34 of the rectangular portion of'the element 29. Each of'the side plates 30 consists substantially of a rectangular plate with a forwardly extended finger 35. The upper edges 3636 of the plates 30 are so formed as to lie in the same horizontal plane with the upper edge 34 of the main element 29, when the parts are assembled as shown in Figure 7 The ;lower edges 3737 of the plates 30 are extended downward slightly below the lower,- most portions of the rack teeth 32 as shown best in Figures 3 and 7; With this construction, it is evident that I form a longitudinally extending groove 38 on the upper side of the rearwardly extended portion of the type bar and a corresponding slot or groove 39 on the lower side of said rearwardly extended arm of the type bar.

The lower slot or groove 39 of each type bar is designed to accommodate the teeth 40 of the corresponding segmental gear D, as clearly shown in Figure 5. Each segmental gear D is also provided with two arcuate side plates 41--41 applied as best shown in Figure 5, the'upper edges of said arcuate plates 41 providing a rolling support in conjunction with the lower edges 37 of the plates 30. With this arrangement, the friction between the segmental gear and each type bar is reduced to a minimum and furthermore each segmental gear is kept in positive alinement with the corresponding rack 31. The various segmental gears D are pivotally supported as indicated at 42 in Figure 2 upon fulcrum plates 43 carried by an arcuate supportingvpressed plate 44- secured at its ends .tothe side walls of the main typewriter frame A. Said plate 44 has an arcuate groove or depression 45 formed in the upper side thereof and in which is disposed a cushioning pad 46 to limit the return movement of the segmental gears and minimizeshocks and vibrations. Each, segmental gear D is formed with a short lever 47 to which is connected one end of a link 48, the opposite end of the'link 48 being pivotally connected to the corresponding key lever E.

The type blocks 24 are slidably supported on the plate 14 and the type bars are guided adjacent the supporting plate 14 by an 'arcuate comb or slotted plate 49 attached by screws orotherwise to the said sub-frame 13. Extending over all of the type bars is an arcuate skeleton bridge plate 5Ov carried at its ends by upstanding plate brackets 51' supported on the main frame of the typewriter. Said skeleton bridge plate has an outer arcuate section 52 and an inner ar cuate section 53. The outer section 52 carries a plurality of guide pins designated generally by the reference character P, there being one of such pins for each type bar C; Each of said guide pins P is in'the form, of'a machine screw 54, the latter at its bottom end having an integral cylindrical point or pin proper 55 of reduced diameter, the'diameter thereof corresponding to the width of the type bar groove or slot 38, as shown in Figure 5. Each of the guide pins P is adjustably threaded to the plate 50 so that the verticalheight of the lower end 56 ofcthe reduced section of the guide pin can be adjusted as will be understood by an inspection of Figure 5. Eachpin may be located in any adjusted position by a lock nut 57.

In the arcuate section ,53 of the skeleton bridge plate 50 is mounted another series of pins designated generally by the reference P. The. latter are vertically adjustably mounted in the plate as will'loe understood and each has a lower fiat bottom face :58 adapted to engage the top edge ofthe type bar including not only the edge 29 of the main elementbut also the edges 36 ofthe plates 30 when the type bar has-been projected to its printing position. It will be noted that the bottom of the pin P is wide enough to extend over the spaced edges 36 of the plates 30 and each pin P may also be locked in adjusted positionby a-lock nut 59.

With the arrangement of guide pin'sP and P, it will be noted that the same may be individually adjusted to compensate'for any variations in the individualtype bars and furthermore that this adjustment may be effected with a maximum'ofconvenience since each of said pins is readilyvaocessible by simply removing the usual cover plate 60 indicated in section in Figure 2. The pins P positivelyprevent any lateral shiftmgor vibration of the type bars. and byadjusting each pair of pins P and P fora V articular type bar, its verticalmovement in all positions thereof between normal and the printing position, can be absolutely controlled. As will be understood by those skilled in the art, the pins P and P can be manufactured at very small expense in large quantitiesbecause of their simple character and the skeletonbrid'ge plate can be drilled and 'threaded'also at very small expense;

In the construction shown inE-Figure S, which is a view corresponding to Figure 5,

the guiding pin P is substantially thesame as the pin P illustrated in Figure but in this instance the bottom section 155 of reduced diameter is made shorter than the depth of the groove or slot 138' of the type bar so that the upper edges of the type bar are controlled by engagement with the face 158 of the larger portion of the pin P in the same manner as in the case of the pin P, previously described; It will be obvious that the arrangement shown in Figure 8 also prevents any possibility of lateral vibration of the type bar.

I have herein shown and described what I now consider the preferred manner of carrying out the invention, butthe same is merely illustrative and I contemplate all changes and modifications that come within the scope of the claims appended hereto.

I claim:

1. In a typewriter, the combination with the typewriter frame including a bridge plate, a reciprocating longitudinally slotted type bar, and means for actuating the type bar; of means for guiding the type bar in its reciprocating movements including, a guide pin individual to the type bar and supported from said plate, said pin having a portion thereof extended within the longitudinal slot of the type bar.

2. In a typewriter, the combination with the typewriter main frame, a reciprocating type bar, and means for actuating the type bar; of means, individual to the type bar and cooperable with the latter, to guide the type bar in its reciprocating movements, said means being individually adjustably supported from a portion of the said frame.

3. In a typewriter, the combination with the main frame, a reciprocating type bar longitudinally slotted along its top edge,

means for actuating the type bar, and a bridge plate extended over the type bar and carried by said frame; of a pin supported by said bridge plate and having its lower end of reduced cross section extending within said slot of the type bar and thereby adapted to guide the latter in its reciproeating movements.

4. In a typewriter, the combination with the main frame, a reciprocating type bar longitudinally slotted along its top edge, means for actuating the type bar, and a bridge plate extended over the typebar and carried by said frame; of a pin supported by said bridge plate and having its lower end of reduced cross section extending within said slot of the type bar and thereby adapted to guide the latter in its reciprocating movements, said pin being adjustably mounted in the bridge plate toward and from the type bar.

5. In a typewriter, the combinaton with the main frame having a type bar action supporting plate; of a reciprocating type gag bar provided with type at one end and with an extended arm at its other end, said arm including a central toothed element and side plates secured thereto and of greater vertical height to thereby form a longitudinally extending groove at the top of said armof the type bar; means for operating said type bar including a segmental gear cooperable with said rack; a bridgeplate carried by said frame and extending over the type bar; and a guide pin, individual to the type baiy vertically adjustably mounted on said bridge plate and having its bottom end ex tended within said slot of the type bar whereby to guide the latter in its reciproeating movements.

6. In a typewriter, the combination with the main frame having a type bar action supporting plate; of a reciprocating type bar provided with type at one end and with an extended arm atthe other end, said arm including a central toothed element and side plates secured thereto and of greater vertical height to thereby form a longitudinally extending groove at the top of said arm of the type bar; means for operating said type bar including a segmental gear cooperable with said rack; a bridge plate carried by said frame and extending over the type bar; a guide pin, individual to the type bar, vertically adjustably mounted on said bridge plate and having its bottom end extended within said slot of the type bar whereby to guide the'latter in its reciprocating move- I ments; and a second guide pin individual to the type bar, and also vertically adjustably mounted on said bridge plate adapted to engage the upper edge thereof.

In a typewriting machine, the combination with a platen and an endwise movable type bar; of bottom supporting and guiding means for the type bar; a bridge plate located above and spaced from the top of the type bar; and a guide, individual to the type bar, depending from said bridge plate and having means cooperable with the type bar to guide the latteragainst vertical upward movement and lateral movement.

8. In a typewriting machine, the combination with a platen and a plurality of endwise movable type bars arranged circularly; of bottom guiding and supporting means for the type bars; a bridge plate located above and spaced from the top of the type bars; and a plurality of guiding elements for the type bars, one for each type bar, each of said guiding elements depending from the bridge plate and having means cooperable with its corresponding type barto guide the latter and prevent vertical upward movement and lateral movement of the type bar.

9. In a typewriting machine, the combination with a platen and a plurality of endwise movable type bars arranged circularly; of bottom guiding and supporting means for r&

the ,type bars; and a plurality of combined top; and lateral guiding elements for the type bars, there, being one of-su'clrelements foreach'type bar, reach of saidelenientsbe ing individually vertically adjustable with respect to its corresponding type "bar. Q A

10. Ina typewriter, the combination with the main iraine having a type bar' action supporting plate; of va reciprocating type bar provided with type at one end and with an extended arm at its other, end, said ex; tended arm containinga central: toothed element and side plates securedftheretd of greater-vertical height Ithan' the central toothed elementto thereby'provide a longitudinally extending groove along the top of said arm ofthe type bargnineans for oper ating. said type bar including a segmental gear eooperablewith said rack; 1 abridge plate carried by said'i'rame' and extending over'the type bar; and a guide piinrindividual to the type bar mounted on said bridge plate and having its bottom end extendingiwithin saidgrooveof thetype bar whereby to guide-:the latter in its reciprocating movement s, 1

v11. As an article of manufacture, atype bar of the longitudinally reciprocating type, said type bar being provided at one end ith an, extended arm, said arm including a central element and-side plates'fsecured on day of October, 1920.

; 12. In a typewriter, the cornbination with i the typewriter frame; of a reciprocating type bar having alongitudinally extending 'guideislot along oneedge thereof; and a guiding element supported, from a part rigid with said frame,said element'projecting ithin saidslotto guide thelatter in its reciprocating movements. 1

'13. lnatypewriter, the combination with a mainframe, areciproc'ating type bar lonior actuating the type bar, and a bridge plate extended .over 'the'type bar and carried byisaidfranne; of a pin supported by gitudinally slotted along its top edge, means said bridge plate and haying its lower. end

dependingbelow thebridge plate and extendin Within said slot of the-type bar to thereby guide the latter in its reciprocating movements- Infwitness that I claimgthe foregoing I have hereunto subscribed my name this 5th Witnesses: c

CARL H. BRUCKER,

FLOYD E. MINER-.3

LEO a niiliiiiis. 

